The French tried the pneumatic railway system at just about the same time, and gave it up for pretty much the same reasons. Those pesky, ravenous rats!

The Beech subway was featured in a National Geographic article several years ago. I don't remember if it's opened for tours on occasion, but the photographs in NatGeo showed one elaborate station, the tilework was just gorgeous!

The Beach [note sp.] subway was featured in a National Geographic article several years ago.

There is a very good, long article on the Web about the history of early 'rapid transit' in New York that covers the Beach proposal (and the machinations by A.T.Stewart, who had extended his store's storage via technically-illegal 'vaults' under Broadway where the Beach tubes would run) - I had the URL on my old computer, which has died, and I can't find it now. Something else of note are the systems designed for quick-build of a couple of the elevated railroad structures, which can be compared even now to things like the Chinese 'bridge-launching' systems for HSR construction. Mike will find it...

A very valid point about this, or any other, vacuum system is that it would handle only a pathetic fraction of the clientele that used, say, one of the elevated trains in New York. There is very little use for a long system that has only one shuttling car or train in service 'backward and forward' through the stations; the Els could routinely operate trains just a few hundred feet apart when necessary either with steam or electric power.

Pneumatics live though, I went to a home improvement show about two months ago and there was an outfit there demonstrating a pneumatically-powered home elevator system. Looked pretty good and it was an interesting demontration.

There is very little use for a long system that has only one shuttling car or train in service 'backward and forward' through the stations; the Els could routinely operate trains just a few hundred feet apart when necessary either with steam or electric power.

From Illistrated Description of the Broadway Undeground Pneumatic Railway 1870

"CARRYING CAPACITY OF THE 'PNEUMATIC RAILROAD. " We have," says Frank Ledie'» Newspaper, " made a little calculation on this point, and find that with two tubes such as that already erected, but perhaps a trifle larger, and with trains starting every two minutes, the company could carry from ten to fifteen thousand passengers per hour from Harlem River to the South Ferry, and probably double that number, should it ever become necessary. At a compara tively moderate rate of speed, the time occupied in traveling the whole distance would not exceed twenty minutes."

"HOW THE CARS STOP AT WAY-STATIONS Another of our views shows the interior of a smai passenger way-station, and illustrates the method о stopping and starting the trains. The tunnel, as i approaches the station, is enlarged, so that air niaj pass the cars, the speed of which is diminished b; the application of brakes. The cars are brought t< a halt within the station, and remain standing upor a slight down-grade, while the air current from on< branch of the tunnel continues on through the statior into the other branch of the tunnel. On releasin« the brakes, the force of the air impinging against th< rear car, assisted by the grade, gently starts th< train forward into the mouth of the tunnel, where il receives the full force of the air-current, and is driven onward to the next station."

But,as with some of the explanations of Hyperloop, and some of Angus Sinclair's sarcastic comments on steam flow in cranks' patent drawings, the 'explanation' does not work so well when scaled up.

Ignore the issues with building a practical 'aeolor' that combines both instantaneous pressure rise far down the tunnel with appropriate mass flow -- even at the 0.6psi differential supposedly effective for the test prototype. Note that the bypass system only works if all the cars operate precisely in sync, and all dwell the same time in stations ... but the only 'wind' downstream of a car moving in a tube is the displaced pressure ahead of it, and this is highly relative to the motion of the car ahead of it. What is likely to develop is a great deal of knocking and stalling, exacerbated when there is any great loss of vacuum/compression sealing at the tube walls.

Now consider the fun if a practical length train, instead of single cars, is used, but the driving power is still proportional to the 'piston area' at one end.

Now calculate the practical acceleration rate for cars starting at any significant distance down the tube...

There are reasons this system didn't, if you'll pardon the pun, go much of anywhere.

On the other hand, I still think there was somewhat more promise in the original Boynton Bicycle idea, turning any standard-gauge track into a full bidirectional right-of-way (with double-deck stack cars and stations but keeping the track available for conventional alternative use... and yes, you could have used Micheline-style self-centering rubber tires with it). Works reasonably well, as long as there are no significant curves...

As the Civil War ended, all of New York City was wedged into the lower third of Manhattan Island. The city was compact, teeming, jammed with more than 700,000 people. Thousands more poured in every day as immigrants and refugees. The streets were clogged with horse-drawn vehicles and traffic moved an inch at a time. Public transportation consisted of overloaded streetcars and omnibuses dragged along by ponderous six-horse teams. Axles broke, horses shied, harnesses became snarled, and competing drivers got into fist fights. Silks and broadcloths were ruined in the crush inside the cars. Watches and breastpins vanished into the hands of pickpockets. The air was poisonous; it was said that a healthy person could not ride a dozen blocks without a headache. Traffic was so dense that it might take an hour to move a few yards. “Modern martyrdom,” one critic summed it up, “may be succinctly defined as riding in a New York omnibus.”

The situation was desperate. What could be done to speed up public transportation?

Suddenly, one fine morning, New York woke up and found that it had a subway.

It was all a little crazy, brilliant, and unbelievable.

The time was February, 1870. New Yorkers read about it in their morning papers.

“A FASHIONABLE RECEPTION HELD IN THE BOWELS OF THE EARTH!” read a headline in the incredulous Herald .

“The waiting room is a large and elegantly furnished apartment, cheerful and attractive throughout,” announced the Sun . “This,” added the Scientific American “means the end of street dust of which uptown residents get not only their fill, but more than their fill, so that it runs over and collects on their hair, their beards, their eyebrows and floats in their dress like the vapor on a frosty morning. Such discomforts will never be found in the tunnel!”

The subway’s waiting room alone astonished reporters. Its frescoed walls, elegant paintings, grand piano, bubbling fountain, and goldfish tank—all were ecstatically described. Then there was the single small car, called “spacious” (it seated twenty-two) and “richly upholstered.” But most of all the press was overwhelmed by the great blowing machine that propelled the car, that sent it “skimming along the track like a sail before the wind” and, once the car had reached the end of the track, calmly drew it back again!

This was the Beach Pneumatic Subway. Its only power was air.

What the journalists were shown, and what 400,000 gawking tourists were to see during the next year, was a cylindrical tube nine feet in diameter, fitting almost as snugly around the single car as a gun barrel around a bullet. A track was laid along the bottom of the tube for 312 feet under the center of Broadway. When the giant fan, called the “Roots Patent Force Blast Blower,” was turned on, it wafted the car down the track at speeds up to ten miles an hour. At the end of the track the car tripped a wire. This reversed the fan, which now “inhaled” the car at the same speed.

The press was excited; so was the public. Not only was the new subway both marvelous and revolutionary, not only did it promise a quick and wondrously unexpected end to the dreadful conditions of street travel, but it caught a shocked city entirely by surprise.

For the Beach Pneumatic Subway was a secret until the moment of its unveiling. No one but its builders even suspected it was there. During fifty-eight successive nights they had burrowed through the earth under Broadway and Warren Street. While the city slept, they stole out of the growing tunnel to dump bags of dirt into wagons whose wheels had been muffled for silence. Other wagons arrived bringing tools, rails, and bricks for the tunnel walls and parts for the car and the mighty wind machine. Night after night gangs of men slipped in and out of the tunnel like thieves.

The street surface was undisturbed. All day, traffic on the busiest thoroughfare of the New World thundered over Mr. Beach’s tunnel. At night the clip-clop of an occasional hansom cab had been plainly audible to the workers beneath.

Beach himself led groups of dignitaries on inspection tours of the tunnel. He was a small, frail man, clean-shaven, with deep-set eyes, a long, thin nose, and a long upper lip. Then forty-four years old, he was well-known as an inventor, patent lawyer, and publisher. He now proposed to run a line to Central Park, about five miles in all. He boasted that when completed it would be able to carry 20,000 passengers a day at speeds up to a mile a minute.

A mile a minute? His listeners gasped. In 1870 nothing went that fast.